Blood pressure recording device

ABSTRACT

A device for recording the blood pressure of a person comprising a cuff adapted to encircle a limb such as an arm of a person. Pressure regulating means is provided to inflate the cuff to a predetermined pressure and to deflate the cuff when the pressure reaches a preselected value. A record is mounted on a movable support, both of which are mounted on the cuff. The support is adapted to move in response to the pressure of said cuff. Writing means is provided for indicating blood pressures on the record. Actuating means responsive to the pulse beats of a person operates the writing means so that the device produces a graphic record of the blood pressure of the person undergoing examination.

United States Patent [72] Inventor Berel Weinstein New York, N.Y.

[21] Appl. No. 749,518

[22] Filed Aug. 1,1968

[45] Patented Jan. 26, 1971 [73] Assignee Bio-Medical Sciences, Inc.

New York, NY.

[54] BLOOD PRESSURE RECORDING DEVICE 11 Claims, 5 Drawing Figs.

[52] US. Cl 128/205 [51] lnt.Cl A61b 5/02 [50] Field of Search 128/205,327; 73/402; 346/(Inquired), 137

[56] References Cited UNITED STATES PATENTS 2,753,863 7/1956 Bailey128/205 3,349,763 10/1967 Clements, Jr. et a1. 128/205 3,480,004 11/1969 Edwards 128/205 FOREIGN PATENTS 792,875 4/1958 Great Britain128/205 Primary Examiner-Charles F. Rosenbaum Assistant Examiner-J. B.Mitchell Attorney-1rving Seidman ABSTRACT: A device for recording theblood pressure of a person comprising a cuff adapted to encircle a limbsuch as an arm of a person. Pressure regulating means is provided toinflate the cuff to a predetermined pressure and to deflate the cuffwhen the pressure reaches a preselected value. A record is mounted on amovable support, both of which are mounted on the cuff. The support isadapted to move in response to the pressure of said cuff. Writing meansis provided for indicating blood pressures on the record. Actuatingmeans responsive to the pulse beats of a person operates the writingmeans so that the device produces a graphic record of the blood pressureof the person undergoing examination.

MICROIPHONF HIGH'GAIN AMPLIFIER 20 5 3 28 so Xfi REGULATOR 18 APPARATUSCO2, 26

TANK

VARIABLE PRESSURE --24 I6 REGULATOR vALvE ExHAUsT4 FIG.2 38

BEREL WEI/VJ TE/N AT TOR NEY BLOOD PRESSURE RECORDING DEVICE Thisinvention relates to a measuring device for measuring the blood pressureof a person and, more particularly, pertains to a device which producesa written record of the blood pressure characteristics of a person.

Presently, blood pressures are measured by means of a device commonlyknown as a sphygnomanometer. In operation, an inflatable cuff is appliedto the arm of the person being examined. The cuff is inflated to aparticular pressure and a stethoscope is placed on the arm of theperson, below the cuff. The pressure in the cufl is released graduallyuntil the first pulse beat is detected by the examiner, therebyindicating the systole. The examiner continues listening to the pulseuntil the intensity of the pulse beat reaches a normal level, therebyindicating the diastole. In view of the fact that the systolic anddiastolic blood pressure points are dependent upon the ability of theexaminer to detect abnormal and normal pulse beats, it is not unnaturalfor two different examiners to read two completely different bloodpressures of the same person although they may be taken at the sametime. Additionally, it requires many years of practice for an examinerto become proficient in detecting pulse beats during blood pressureexaminations. Furthermore, it has been found that the ambient noiselevel affects blood pressure readings since it becomes difficult todetermine the point at which the pulse beat becomes normal in noisysurroundings. Accordingly, it has been found to be practicallyimpossible to take accurate blood pressure readings in wards or thelike.

In addition to the above, further disadvantages associated withsphygnomanometers reside in the fact that the examiner is required tomanipulate the pressure valves associated with the cuff simultaneouslywith the reading of the device, thereby further increasing thedifficulty of taking accurate readings. Moreover, after taking thereadings, the examiner usually is required to transcribe the readingsonto a chart. Hence, there is additional room for error due to errors intranscribing the infonnation.

Accordingly, an object of the present invention is to provide animproved device for taking the blood pressure of a person.

Another object of the invention is to provide a blood pressure devicewhich provides the examiner with a permanent record of the systolic anddiastolic pressures.

A further object and feature of the invention resides in the noveldetails of construction which provide a blood pressure device of thetype described wherein the systole and diastole are automatically andaccurately determined.

Another object of the present invention is the provision of a reliableblood pressure indicating device which is compact and relatively easy touse.

Accordingly, a blood pressure recording device constructed in accordancewith the present invention includes pressure means for applying pressureto an area of the body. Record means having pressure points designatedthereon is provided and writing means responsive to the intensity of thepulse beats of a person is adapted to produce the systole and diastoleon the record. Additionally, the device includes mov ing means formovingone of the writing means or the record relative to the other inresponse to the pressure of said pressure means thereby to produce aperrnanent'record of the blood pressure of the person being examined.

Other features and advantages of the present invention will become moreapparent from a consideration of the following detailed description whentaken in conjunction with the drawing, in which:

FIG. 1 is a top plan view of a blood pressure recording deviceconstructed in accordance with the present invention;

FIG. 2 is an enlarged detailed view, partially in schematic form, of thewriting mechanism of the present invention;

FIG. 3 is a block diagram of the pressure system of the invention;

FIG. 4 is a schematic circuit wiring diagram, partially in block diagramform, of the electrical portion of the invention; and

FIG. 5 is a perspective view of the device on the arm of a patient.

Accordingly, a blood pressure recording device for graphicallydetermining the blood pressure of a person is shown in FIG. I anddesignated generally by the reference numeral 10. The device 10 includesa conventional cuff I2 that is adapted to be wrapped about a limb suchas the arm of the person to be examined, and to be secured thereto.Within the cuff I2 is a chamber (not shown) that is adapted to be filledwith a fluid under pressure, such as air, to apply a pressure to the armof the person. Received on the cuff I2 is a housing 14 which containsthe means for inflating the cuff and recording the blood pressure.

More particularly, the housing 14 contains a source of fluid underpressure such as a cartridge I6 containing carbon dioxide underpressure. (See FIG. 3) The tank 16 is connected to the cuff 12 by aconduit 18 through a shutoff valve 20 and a normally open variablepressure regulating valve 22. The cuff l2 exhausts to the atmospherethrough another normally closed variable pressure regulating valve 24via a conduit 26. Also communicating with the cuff 12, by means of aconduit 28, is a record moving apparatus designated generally by thereference numeral 30.

The record moving apparatus 30 includes an aneroid-type mechanism 32having a rotatable platform or support 34. The mechanism 32 is adaptedto rotate the platform 34 in accordance with the pressure of the cuffI2. That is, the angular position of the platfonn 34 will be dependentupon the pressure of the cuff I2 since the aneroid-type mechanism isresponsive to the value of pressure in the cuff. Hence, as the pressurevaries in the cuff, the angular displacement of the platform relative toa particular reference point will likewise vary. The mechanism 32 is ofconventional construction and, accordingly, is not disclosed in detailherein.

Mounted upon the platform 34 is a record which is adapted to be movedpast a writing station designated generally by the reference numeral 38.More particularly, the record 36 comprises a disc having graduations 40thereon which correspond to different values of pressure. Complementaryformed indexing means between the disc 36 and the platform 34 insurethat the disc will be mounted on the platform in one orientation only.Thus, upstanding from the platform 34 are spaced posts 42 and 44. Thepost 44 is larger in diameter than the post 42. Provided in the disc arespaced openings which are respectively sized to receive the posts 42 and44 to insure that the disc is properly mounted on the platform. When therecord 36 is so mounted on the platfonn 34, the pressure graduationbelow the writing station 38 corresponds to the pressure of the cuff 12.Hence, the record 36 provides a means for calibrating the cuff 12.Additionally, it will be apparent that the record 36 easily may bereplaced by another record. Hence, when the blood pressure of a personis taken, in the manner noted below, that particular record is replacedwith a blank record thereby providing the examiner with a permanentrecord of the examination.

The writing station 38 (FIG. 2) includes a housing 46 mounted above therecord 36 which has an open bottom. Received within the housing 46 is asolenoid winding 48 having movable core 50. Connected to the bottom ofthe core 50 by a set screw or the like, is a pen 54 of the type whichcontains its own'well so that it will hold an ink supply for arelatively long interval. When the solenoid is energized, the core 50 iscaused to move downwardly until the pen 54 engages the record 36 therebyleaving a mark on the record. Since the portion of the record below thewriting station 38 corresponds to the pressure of the cuff I2, the markleft on the record 36 by the pen 54 will indicate the pressure of thecuff at that particular instant.

The circuit which energizes the solenoid 48 includes a transducer in theform of a microphone 56. The microphone 56 is positioned in the cuff 12so that it will detect pulse beats and convert the pulse beats intoelectrical signals. As shown in FIG. 4, the microphone 56 is connectedto a relatively high gain amplifier 58. The gain of the amplifier andthe characteristics of the microphone are selected so that the amplifierwill produce an output signal only when the intensity of the pulse beatis equal to or higher than the diastolic pulse beat.

Connected to the output of the amplifier 58, through a blockingcapacitor 60, a voltage divider comprising a resistor 62 and a resistor64 (one end .of which is connected to ground) and a diode 66 is aso-called Darlington pair of transistors 68 and 70. The anode of thediode 66 is connected to the junction of the resistors 62 and 64, thecathode of the diode 66 is connected to the base electrode of thetransistor 68. The emitter electrode of the transistor 68 is connectedto the base electrode of the transistor 70. The emitter electrode 70 isconnected to ground. The collector electrodes of the transistors68 and70 are connected together and to the positive terminal of a source ofpotential 72 (the other terminal of which is grounded) through thesolenoid winding 48. As is well known in the art, this particular typeof circuit connection provides a great current amplification to insureoperation of the solenoid 48 and the pen 54 thereby. Hence, pulse beatsfalling within the range of intensities noted above cause a signal toappear at the output terminals of the amplifier 58. These signals areamplified by the transistors 66 and 70 to energize the solenoid 48 tooperate the pen 54.

In operation, the controls 24A and 22A of the respective variablepressure regulating valves 24 and'22 are set by tuming the dials on thehousing M (FIG. 1) to the proper pressures. The cuff 12 is then wrappedaround the arm, for example, of theperson to be examined and is affixedthereto by any conventional means. A switch may be operated then toenergize the electric circuit elements. (This switch is not shown inFIG. 4 but it is to be understood it is connected in series with thesource 72.) Thereafter the valve is operated to connect the tank 16 tothe cuff 12. Accordingly, the cuff l2 inflates until the pressure of thecuff operates the valve 22 which closes to prevent further increases inthe pressure. As the pressure of the cuff increases, the platform 34rotates the record 36 past the writing station 38 so that the recordreflects the increased pressure in the cuff 12. In practice, the valve241 is set to open at the pressure the valve 22 is set to close, so thatthe fluid will begin to be exhausted to the atmosphere when the valve 22closes. Moreover, this pressure is set substantially above the systolicpressure so that no pulse will be detected until the pressure begins todrop.

As the pressure of the cuff 12 drops, the platform and, therefore, therecord 36 begin to rotate in the opposite direction .to indicate thelower pressure. When the systolic pressure is reached, the pulse beat isdetected by the microphone 56 to cause the pen 54 to engage the record36 in the manner noted above. Accordingly, since the graduationrepresenting the pressure then in the cuff is below the writing station38, the systole will be indicated. Moreover, as the pressure continuesto decrease, the pen will be caused to engage the record 36 at eachsucceeding pulse beat thereby producing a series of marks on the record.That is, as the pressure decreases, the graduations representingdecreasing pressures pass below the writing station 38 so that the pen54 engages different portions of the record 36. Finally, when thediastole is reached, no further marks will be made on the record since,as noted above, the device is responsive to pulse intensities equal toor above the pulse beat representative of the diastolic pressure. Thus,the record 36 then may be removed to provide the examiner with apermanent record of the blood pressure of the person undergoingexamination.

At this point a new record 36 may be placed on the platform 34, in theproper orientation, and the device again may be utilized to produce apermanent record of the blood pressure of another person.

Accordingly, a blood pressure recording device has been disclosed whichis compact and reliable in operation and which does not rely on theexaminer to determine the systole and diastole.

While a preferred embodiment of the invention has been shown anddescribed herein, it will be obvious that numerous omissions, changesand additions may be made in such embodiment without departing from thespirit and scope of the present invention.

lclaim:

l. A device for recording the blood pressure of a person comprising acuff adapted to encircle a limb of the body; a housing on said cuff;pressure regulating means in said housing for regulating the pressure insaid cuff; recording means on said housing, said recording meansincluding a record having pressure points designated thereon and furtherincluding writing means responsive to the intensity of the pulse of theperson for producing, on said record, the systole and diastole; andmoving means for moving one of said record and writing means relative tothe other in response to the pressure of said cuff.

2. A device for recording the blood pressure of a person as in claim 1,in which said regulating means including first valve means adapted to beconnected between a source of fluid under pressure and said cuff andbeing responsive to a first preselected pressure of said cuff forshutting off the flow of fluid from the source to the cuff, and secondvalve means responsive to a second preselected pressure in said cuff forexhausting the pressurized fluid in said cuff to deflate the cuff.

3. A device for recording the blood pressure of a person as in claim 1,in which said moving means includes support means for supporting saidrecord whereby said moving means moves said record relative to saidwriting means.

4. A device for recording the blood pressure of a person as in claim 1,in which said writing means includes an indicating device, mountingmeans for mounting said indicating device above said record, and circuitmeans including electromechanical means for moving said indicatingdevice into engagement with said record in response to the pulse beatsof a person.

5. A device for recording the blood pressure of a person as in claim 4in which said circuit means includes a transducer for converting pulsebeats into electrical signals, amplifying means for amplifying saidelectrical signals, said electromechanical means comprising a solenoidhaving a core movable in response to the energization of said solenoid,connecting means for connecting said indicating device to said solenoid,whereby said solenoid causes said indicating device to engage saidrecord in response to said electrical signals.

6. A device for recording the blood pressure of a person as in claim 5,in which said moving means includes a rotatable record support adaptedto removably receive said record thereon and to rotate said record belowsaid indicating device in response to the pressure of said cuff, andcooperable'indexing means on said record and said record support formounting said record on said record support in a preselectedorientation.

7. A device for graphically determining the blood pressure of a personcomprising a cuff adapted to encircle the limb of a person, a housing onsaid cuff, pressure regulating means in said housing for selectivelyinflating said cufi' to a predetermined pressure and for depressurizingsaid cuff when the pressure reaches a preselected value, a writingstation having a writing device on said housing, record means on saidhousing movable past said writing station in response to the pressure ofsaid cuff, said record means including calibration means for designatingthe different pressures of said cuff whereby the pressure designationcorresponding to the pressure of said cuff is positioned below saidwriting station, and actuating means for operating said writing deviceto engage said record means in response to pulse beats.

8. A device for graphically determining the blood pressure of a personas in claim 7, in which said pressure regulating means includes a firstpressure regulating valve adapted to connect a source of fluid underpressure to said cuff and to disconnect said source when the pressurereaches said predetermined pressure, and a second pressure regulatingvalve for exhausting the pressurized fluid from said cuff when thepressure in said cuff reaches said preselected level.

9. A device for graphically determining the blood pressure of a personas in claim 8, in which said first and second pressure regulating valvesare variable.

11. A device for graphically determining the blood pressure of a personas in claim 7, in which said record means comprises a support movable inresponse to the pressure of said cuff, and said calibration meansincludes a record removably supported on said support and rotatabletherewith, and indexing means between said support and said record formounting said record on said support in predetermined orientation only.

1. A device for recording the blood pressure of a person comprising acuff adapted to encircle a limb of the body; a housing on said cuff;pressure regulating means in said housing for regulating the pressure insaid cuff; recording means on said housing, said recording meansincluding a record having pressure points designated thereon and furtherincluding writing means responsive to the intensity of the pulse of theperson for producing, on said record, the systole and diastole; andmoving means for moving one of said record and writing means relative tothe other in response to the pressure of said cuff.
 2. A device forrecording the blood pressure of a person as in claim 1, in which saidregulating means including first valve means adapted to be connectedbetween a source of fluid under pressure and said cuff and beingresponsive to a first preselected pressure of said cuff for shutting offthe flow of fluid from the source to the cuff, and second valve meansresponsive to a second preselected pressure in said cuff for exhaustingthe pressurized fluid in said cuff to deflate the cuff.
 3. A device forrecording the blood pressure of a person as in claim 1, in which saidmoving means includes support means for supporting said record wherebysaid moving means moves said record relative to said writing means.
 4. Adevice for recording the blood pressure of a person as in claim 1, inwhich said writing means includes an indicating device, mounting meansfor mounting said indicating device above said record, and circuit meansincluding electromechanical means for moving said indicating device intoengagement with said record in response to the pulse beats of a person.5. A device for recording the blood pressure of a person as in Claim 4,in which said circuit means includes a transducer for converting pulsebeats into electrical signals, amplifying means for amplifying saidelectrical signals, said electromechanical means comprising a solenoidhaving a core movable in response to the energization of said solenoid,connecting means for connecting said indicating device to said solenoid,whereby said solenoid causes said indicating device to engage saidrecord in response to said electrical signals.
 6. A device for recordingthe blood pressure of a person as in claim 5, in which said moving meansincludes a rotatable record support adapted to removably receive saidrecord thereon and to rotate said record below said indicating device inresponse to the pressure of said cuff, and cooperable indexing means onsaid record and said record support for mounting said record on saidrecord support in a preselected orientation.
 7. A device for graphicallydetermining the blood pressure of a person comprising a cuff adapted toencircle the limb of a person, a housing on said cuff, pressureregulating means in said housing for selectively inflating said cuff toa predetermined pressure and for depressurizing said cuff when thepressure reaches a preselected value, a writing station having a writingdevice on said housing, record means on said housing movable past saidwriting station in response to the pressure of said cuff, said recordmeans including calibration means for designating the differentpressures of said cuff whereby the pressure designation corresponding tothe pressure of said cuff is positioned below said writing station, andactuating means for operating said writing device to engage said recordmeans in response to pulse beats.
 8. A device for graphicallydetermining the blood pressure of a person as in claim 7, in which saidpressure regulating means includes a first pressure regulating valveadapted to connect a source of fluid under pressure to said cuff and todisconnect said source when the pressure reaches said predeterminedpressure, and a second pressure regulating valve for exhausting thepressurized fluid from said cuff when the pressure in said cuff reachessaid preselected level.
 9. A device for graphically determining theblood pressure of a person as in claim 8, in which said first and secondpressure regulating valves are variable.
 10. A device for graphicallydetermining the blood pressure of a person as in claim 7, in which saidactuating means includes circuit means responsive to pulse beats ofintensity equal to or higher than the diastolic pulse beat forconverting the pulse beats of a person into electrical signals, and asolenoid having a core connected to said writing device for moving saidwriting device into engagement with said record means in response to theenergization of said solenoid by said electrical signals.
 11. A devicefor graphically determining the blood pressure of a person as in claim7, in which said record means comprises a support movable in response tothe pressure of said cuff, and said calibration means includes a recordremovably supported on said support and rotatable therewith, andindexing means between said support and said record for mounting saidrecord on said support in predetermined orientation only.